San-Francisco-based studio Peek Ancona has designed the Flood-Proof House in Stinson Beach, California, USA.
Flood-Proof House by Studio Peek Ancona:
A built flood-proof prototype for flood zones worldwide: a building that remains intact after a major flood, tsunami, or sea level increase.
A sustainable kit of parts with a prefab steel frame and local cladding materials is designed for both local customization and global application.
Plug-in adaptability: the central cantilevered truss provides an architectural “plug” as a solution to the client’s request to preserve the adjacent historic house. The truss functions as a circulation core and bridge for site expandability.
Marin County certified Platinum for sustainable design, including an innovative foundation system that uses thirty percent less materials than current flood-resistant buildings.
The high flood hazard zone of Stinson Beach, CA, which must comply with most recent FEMA standards.
Located one quarter mile from the San Andreas Fault.
The site contains a small 1940 mid-century modern beach house on half of the lot.
Program and Codes:
Small built area: second floor enclosed space is 450 sq.ft., with 350 sq.ft. of cantilevered decks creating “borrowed spaces” for interiors.
A dramatic base flood elevation (BFE) of 12’ allows a storm-driven flood or tsunami to thrust under this height.
Cantilevered second floor: master bedroom, sun court, master bath, and four view decks above BFE. A new recreation area is provided in the breakaway flood area under the new house. Original indoor/outdoor dining and living rooms are located in existing house.
Client request to achieve maximum sustainability and minimum site alteration is addressed through innovative uses of structure and materials.
Composite foundation: a steel anchoring system is combined with a concrete thickened edge foundation, providing usable recreation and/or parking space on the ground floor (subject to seasonal flooding). The foundation is light enough that it floats in the wet soil, but heavy enough with the hybrid anchor/perimeter system that it resists waves above. The foundation provides an alternative to typical piers that often measure forty feet underground.
Interlocking horizontal steel moment frame and truss system: this maximizes usable space above the flood level, cantilevering atop the wave-proof columns. The frame is prefabricated, shipped in sections, and assembled on site. The perpendicular steel truss enables the new house to cantilever over the existing house as a code exception to preserve the adjacent historic house.
Western Red Cedar “ventilated-wall” façade is a high-tech application using low-tech renewable materials: air is circulated under this cladding, creating additional insulation and a rainscreen barrier. The cedar detailing provides an aesthetic complement to the eclectic context of mid-century and rustic Northern California buildings.
Two tall glass “barn doors” are hung on the exterior of the upper floor, providing natural ventilation, access to decks, and sweeping views west to the ocean, and east to the coastal range.
In the prototype version, ground floor bi-fold walls automatically retract allowing waves to roll beneath. For future sea level increases, bi-folds can be left in up position as docks for boat access.
Interior finishes include radiant-heated bamboo flooring, blue slate accents, and muted green walls to balance the warm cedar and steel greys, an aesthetic accentuating this northern edge of the Pacific.”
Photos by: Bruce Damonte